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--- baboons [2014/06/09 16:44]
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-This is the project page for BaBooNs.
+**This is the project page for BaBooNs. **
 Kaitlin Cook: Parameters
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 Rob Almus: Analysis
-Investigate the effects of non-thermal baryon injection on BBN.
+**Aim**: Investigate the effects of non-thermal baryon injection on BBN.
+**Introduction**
+If dark matter particles (e.g. WIMPS) exist, they inevitably did so during the big bang. They also may decay during BBN into non-thermal particles - this may be in the form of photons, leptons (electron/positron pairs and/or neutrinos) or into hadronic channels (n/p, mesons, nuclei). These decays may have two influences into BBN:
+) Change the expansion rate due to the injection of relativistic species.
+) Effect the abundance of light nuclei produced in BBN via reactions with these decay particles.
+In case (1), this effect is important only if the decay channels are relativistic, thus adding a lot of entropy into the universe. In this project, we will consider the injection of neutrons, so we will not consider this effect.
+It is thus the goal of this project to investigate the effect of the injection of non-thermal neutrons on the light element abundances.
+**Key parameters: **
+  - The mean life of the decaying particle X -> 2n  (some magic decay. Not very physical, probably. But hey, we don't actually know what WIMPS are).
+  - The energy of these neutrons (although if it is high enough, it may not matter too much?)
+  - The abundance of X. Jedamzik, 2004: 7Be is suppressed if O(10^-5) neutrons per proton are injected. Increases D/H. Lifetime of ~1000 s required.
+  - n interaction rates with every other nucleus.
+  - Mass of the WIMP. Chosen to be 100 GeV, based on the wikipedia WIMP entry, the font of all wisdom.
+This figure:
+{{::cdms_parameter_space_2004.png?600|}}
+from CDMS in 2004 suggests that this value isn't too far off.
+Reference Papers:
+Cyburt et. al. 2009. Nucleosynthesis Constraints on a Massive Gravitino in Neutralino Dark Matter Scenario [[http://arxiv.org/pdf/0907.5003v1.pdf]]
+Kamionkowski 1994. Diffuse Gamma Rays from WIMP Decay and Annihilation [[http://arxiv.org/pdf/astro-ph/9404079v1.pdf]]
+Pierre Salati, 2014. Dark Matter Annihilation in the Universe [[http://arxiv.org/pdf/1403.4495.pdf]]
+**Logbook**

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